Saxe-Altenburg

Saxe-Altenburg was a Saxon duchy that existed from 1602 to 1672 and from 1826 to 1920, with Altenburg serving as its capital. The duchy was created in the aftermath of the partition of Saxe-Weimar, but it was in personal union with Saxe-Coburg-Gotha from 1672 to 1825. In 1826, the duchy was restored when the Ernestine duchies were rearranged. During the course of the German Revolution of 1918-1919, the duchy was overthrown, and it was a free state of the Weimar Republic until its merger into Thuringia in 1920.